Transformer operated energy meters need instrument transformers to reduce high voltage- and current values to lower quantities for measurement purpose.
Each conductor wire has a resistance. Resistance means heat development inside the wire. Technically it’s a loss.
The critical change value indicates the maximum amount of change allowed in the meter’s energy registers during disturbance tests without any current flowing in the meter’s current circuits.
With publishing of the Edition 2 of IEC62052-11 the minimum run time calculation formula has changed.
The main purpose of an electronic energy meter is the accurate metering of the customer consumption. The meter has registers for storing the various consumption values
Each energy meter used for billing must have a test output. An optical indication is mandatory. Beside this the meter can also have electrical test outputs.
We have a nice three phase power supply in our home, but where does it come from? And why does the waveform has a sine shape?
The interactive diagram below shows the relationship between the phase angle φ, apparent-, active- and reactive power respective energy in accordance with clauses 12 and 14 of IEC 60375.